Pentane → 5-Diallylaminomethyl-thiophene-2-sulfonyl chloride

HRID 2113733Notes

Reaction equation

HRID 2113733 reaction equation
ClC1C(NCCCC(NN[S:20]([C:23]2[S:27][C:26]([CH2:28][NH:29][C:30](=O)[C:31]3[CH:36]=CC([N+]([O-])=O)=CC=3)=[CH:25][CH:24]=2)(=[O:22])=[O:21])=O)=NC=C(C(F)(F)F)C=1.[Li][C:42]([CH3:45])(C)[CH3:43].CCCCC.C1C(=O)N([Cl:58])C(=O)C1>CCOCC.C1COCC1>[CH2:43]([N:29]([CH2:28][C:26]1[S:27][C:23]([S:20]([Cl:58])(=[O:21])=[O:22])=[CH:24][CH:25]=1)[CH2:30][CH:31]=[CH2:36])[CH:42]=[CH2:45]

Participants

7

Conditions

Temperature
-70 °C

Procedure

A solution of the allyl-protected thiophene 19a (6.2 g, 32.1 mmol) in Et2O was cooled to −70° C. by means of an acetone/dry ice bath. A solution of t-BuLi in pentane (21.38 ml, 1.5M, 32.1 mmol) was added over 2 min whereupon the internal temperature momentarily rose to −50° C. and the mixture turned orange. After 10 min., SO2 was bubbled for 2 min, which led to the immediate formation of a thick precipitate. The reaction was allowed to reach 0° C., and a suspension of NCS (4.63 g, 32.1 mmol) in THF (20 ml) was added, whereupon the slurry turned purple. After 45 min at r.t., the mixture was filtered over SiO2, eluting with EtOAc. Evaporation, dilution with EtOAc:hexane 1:5 and filtration over SiO2 gave 5.0 g (53%) of the title sulfonyl chloride 19b as a pale brown oil which was used without further purification.

Workup

  1. custommomentarily rose to −50° C.
  2. customSO2 was bubbled for 2 min
  3. customto reach 0° C.
  4. additionwas added, whereupon the slurry
  5. waitAfter 45 min at r.t.
  6. filtrationthe mixture was filtered over SiO2
  7. washeluting with EtOAc
  8. customEvaporation, dilution
  9. filtrationwith EtOAc:hexane 1:5 and filtration over SiO2

Sources & evidence

ORD record
ord-0a46cfb1cc904262b085e15aa3a734f5
Source dataset
uspto-grants-2008_10
Patent number
US07432286B1

Reaction notes

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